Respuesta :
By Friday he should have done 20 sit-ups because every day he is doing 4 more than the last.
Answer: 20 sit ups.
Step-by-step explanation: if tyrell does situps everyday on monday he does 4 sit ups and tuesday 8 situps wendsday 12 situps thursday 16 situps friday 20 situps all u do to solve is add 4 every day.
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